Antiischemic

Antiischemic refers to therapies and agents aimed at preventing or treating myocardial ischemia by either reducing the heart’s oxygen demand or increasing the coronary supply of oxygen. In cardiovascular care, antiischemic strategies are central to managing conditions such as stable angina and acute coronary syndromes, with goals including relief of chest pain, improved exercise tolerance, and reduction of ischemia-related complications.

Mechanisms of action include decreasing myocardial oxygen demand—via reduction of heart rate, contractility, and blood pressure with beta-blockers and certain calcium channel blockers; nitrates reduce preload (and to some extent afterload) to lower wall stress; metabolic agents such as ranolazine decrease diastolic wall tension and shift myocardial metabolism toward more efficient energy use. Increasing oxygen supply is achieved mainly by vasodilation of coronary arteries with nitrates and some calcium channel blockers, which can relieve flow limitation or vasospasm.

Representative antiischemic agents include nitrates (nitroglycerin, isosorbide dinitrate), beta-adrenergic blockers (metoprolol, atenolol), calcium channel blockers (amlodipine, diltiazem), and ranolazine. These drugs are used alone or in combination to manage symptoms of chronic coronary disease and to stabilize patients during acute coronary events, often as part of a broader strategy that includes antiplatelet therapy, lipid lowering, and reperfusion when indicated.

Limitations and considerations include adverse effects such as hypotension, bradycardia, headaches, or constipation, and tolerability issues with some agents. Antiischemic therapy forms part of evidence-based guidelines for coronary artery disease and should be tailored to individual risk factors and clinical context.